Physics and Astronomy Publications
Document Type
Article
Publication Date
2018
Journal
The Journal of Physical Chemistry
Volume
122
Issue
18
First Page
10167
Last Page
10172
URL with Digital Object Identifier
https://doi.org/10.1021/acs.jpcc.8b02301
Abstract
The frequency of localized surface plasmon resonance (LSPR) displayed by gold nanoparticles (AuNPs) redshifts as a function of their local refractive index, which renders them valuable transducers for sensing applications. An ensemble hypothesis is presented herein, along with spectroscopic evidence, using the biotin-streptavidin system on immobilized AuNPs to interpret the decrease in ensemble linewidth (ELW) consistently observed upon functionalization of plasmonic nanoparticles and the subsequent analyte binding. These results demonstrate that ELW can be used to monitor recognition reactions, providing spectral details and a possible sensitivity enhancement to the conventional wavelength sensing. A novel sensing platform allowing the simultaneous measurement of both LSPR wavelength and ELW is proposed, which not only combines the advantages of both parameters but also permits real-time measurement and miniaturization.